WEED SCIENCE
·
2025
·
IF 2.5
Shaojing Yin,Guangtao Zhu,Yiheng Li,Liyao Dong,Zhike Feng
Italian ryegrass [Lolium perenne L. ssp. multiflorum (Lam.) Husnot], a pernicious weed in wheat fields, has evolved severe resistance to the acetolactate synthase (ALS)-inhibiting herbicides, like pyroxsulam. Here, the derived cleaved amplified polymorphic sequence (dCAPS) markers were developed to detect two distinct mutations at the 197th position of the ALS gene. The method was used to examine and purify the resistant population. Homozygous populations with different 197 site mutations from the same population were obtained, and the target-site resistance mechanisms were investigated. Whole-plant dose-response bioassays show that the resistance index (RI) of the Pro-197-Thr mutant population to pyroxsulam was 508.92, whereas that of the Pro-197-Gln population was 9.75. Similar trends were observed for different herbicides within same mode of action. In vitro ALS assays demonstrated that the Pro-197-Thr population exhibited lower sensitivity to pyroxsulam than the Pro-197-Gln population, consistent with plant bioassays. Furthermore, ALS gene expression of the Pro-197-Thr population analysis is significantly higher than that in the Pro-197-Gln population which may also explain why the Pro-197-Thr population exhibits higher resistance level than the Pro-197-Gln population. Our findings suggest that different amino acid substitutions at one ALS gene locus can confer herbicide resistance with different levels in L. perenne ssp. multiflorum. This study provides valuable insights into the mechanisms of herbicide resistance in L. perenne ssp. multiflorum.
研究领域:
植物学
·
植物科学
·
杂草科学
·
分子生物学
·
遗传学
·
农学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
·
2022
·
IF 3.841
Chengcheng Tang,Yiran Song,Zhuang Wang,Da Wang,Xinyu Yao,Yuan Meng,Yang Li,Li Yang
Growing multidrug bacterial resistance has become a life-threatening problem. Polymyxins are a “last resort” antibiotic against Gram-negative bacteria (Gram-ne − ), but exhibit weak activity against Gram-positive bacteria (Gram-po + ) caused by different bacterial membrane structures. Herein, it is proposed that the challenge can be overcome by hydrophobically modified polymyxin E for enhancing the hydrophobic interaction with the membrane. After synthesizing mono-and di-fatty acyl conjugates to Thr residues of polymyxin E, seven new polymyxin analogs were screened out with in vitro activity against Gram-ne − and Gram-po + . Among them, di-caprylic acid-modified (comp. 2 ) and mono-linoleic acid-modified (comp. 3) compounds with the most potent activity against both bacteria. Moreover, the membrane research showed that polymyxin analogs obtain activity against Gram-po + by higher ability to dispute cell membrane and wall than polymyxin E. Additionally, the results showed a trend of increasing hydrophobicity of analogs showing the tendency to rise up at the beginning and declining in later against Gram-po + and gradually decreasing activity against Gram-ne − , hence, we speculated that controlling Log P at 1–3 helps to obtain broad-spectrum antibiotic. Crucially, the maximum tolerated doses (MTD) of analogs were significantly higher than polymyxin E, and reduced the nephrotoxicity. As expected, hydrophobic modification polymyxin E not only enhance the activity of Gram-po + , but also could retain the activity of Gram-ne − . This study offers more insights into the synthesis of new antibiotics based on polymyxin E structure, especially broad-spectrum antibiotics.
研究领域:
微生物学
·
药理学
·
生物化学
✓ 已验证
DOI
高影响因子
Communications Biology
·
2026
·
IF 5.8
Lu Yiping,Wang Chongyang,Zhang Keke,Zhang Zhichao,Xu Huifang,Wu Danni,Zhao Kun,Ma Honglei,Lu Xuefeng
Coordinating phosphate acquisition with overall nutritional status is critical for cyanobacterial survival in oligotrophic environments, yet the molecular basis for substrate selectivity in phosphate-binding proteins (PBPs) remains incompletely understood. Here we reveal two evolutionarily distinct PBP architectures in Synechocystis sp. PCC 6803 through integrative structural and biochemical analyses. High-resolution crystal structures (1.76–1.9 Å) of PstS1 and SphX bound to inorganic phosphate (Pi) demonstrate that D-type PBPs utilize a conserved aspartate-mediated low-barrier hydrogen bond (LBHB) for high-affinity Pi binding (nanomolar Kd), whereas S-type SphX employs a previously uncharacterized Asp-Arg-Thr catalytic triad with reduced affinity (micromolar Kd). Despite forming comparable hydrogen bonding networks (14 versus 15 bonds), SphX exhibits 26-fold lower Pi affinity due to threonine-mediated proton acceptance replacing the LBHB mechanism. Systematic mutagenesis confirms the functional importance of each triad residue and indicates partial compensation by neighboring residues. Phylogenetic analysis demonstrates that these architectural variants are conserved across cyanobacterial lineages, representing adaptive solutions to diverse nutrient-limited environments. Our findings establish a mechanistic framework for understanding PBP functional diversification and provide molecular insights relevant to optimizing cyanobacterial productivity in biotechnology applications.
✓ 已验证
DOI
PubMed
高影响因子
Life Science Alliance
·
2024
·Vol. 7
·期 4
·e202302375
·
IF 3.3
Jialing Bao,Yunlin Tang,Yebo Chen,Jiangyan Jin,Xue Wang,Guozhen An,Lu Cao,Huarui Zhang,Gong Cheng,Guoqing Pan,Zeyang Zhou
Microsporidia are difficult to be completely eliminated once infected, and the persistence disrupts host cell functions. Here in this study, we aimed to elucidate the impairing effects and consequences of microsporidia on host DCs. Enterocytozoon hellem, one of the most commonly diagnosed zoonotic microsporidia species, was applied. In vivo models demonstrated that E. hellem-infected mice were more susceptible to further pathogenic challenges, and DCs were identified as the most affected groups of cells. In vitro assays revealed that E. hellem infection impaired DCs’ immune functions, reflected by down-regulated cytokine expressions, lower extent of maturation, phagocytosis ability, and antigen presentations. E. hellem infection also detained DCs’ potencies to prime and stimulate T cells; therefore, host immunities were disrupted. We found that E. hellem Ser/Thr protein phosphatase PP1 directly interacts with host p38α (MAPK14) to manipulate the p38α(MAPK14)/NFAT5 axis of the MAPK pathway. Our study is the first to elucidate the molecular mechanisms of the impairing effects of microsporidia on host DCs’ immune functions. The emergence of microsporidiosis may be of great threat to public health.
研究领域:
免疫学
·
微生物学
·
病理学
✓ 已验证
DOI
PubMed
高影响因子
ACS Applied Bio Materials
·
2021
·
IF 0
Wen Liu,Xiao Yang,Pengpeng Li,Feng Sang,Lina Cao,Bingxu Zhang,Zhizhen Meng,Zhaipu Ma,Changcan Shi
Uncontrollable hemorrhage, especially uncompressible and massive hemorrhage, is life threatening. To develop a kind of hemostatic material that is biocompatible and has effective hemostatic performance, a starch-polyethylene glycol sponge (St-PEG sponge) incorporated with electrospraying microspheres made from carboxymethyl chitosan and sodium alginate (CMC/SA eMPs) is employed to fabricate the topical hemostatic agent for application. To load thrombin safely and effectively, CMC/SA eMPs encapsulating thrombin compounds (eMPs@Thr) are further incorporated with St-PEG sponge to obtain eMPs@Thr/sponge. The results show that eMPs@Thr/sponge could obviously reduce blood loss and shorten the hemostatis time compared with commercial hemostatic products Kuai Kang. The construction of the eMPs@Thr/sponge could not only maintain the expandable properties of the St-PEG sponge but also strengthen the procoagulant activity. Therefore, this work provides a facile approach for loading thrombin given the fact that thrombin suffers from instability and risk of thrombus. It is predicted that eMPs@Thr/sponge might hold great potential in uncompressible and massive hemorrhage control.
研究领域:
生物材料
·
止血
·
生物医学工程
·
组织工程
✓ 已验证
产品关联
DOI
PubMed
JOURNAL OF HAZARDOUS MATERIALS
·
2020
·
IF 9.038
Wenjuan Zhang,Aijing Li,Yu Pan,Fengbang Wang,Ming Li,Yong Liang,Xinglei Yao,Jinghai Song,Maoyong Song,Guibin Jiang
Tetrabromobisphenol A (TBBPA) is a widely used flame retardant , but the adverse outcomes induced by TBBPA has not been fully elucidated. In this study, TBBPA was detected in 54.9% of 102 female Chinese volunteers with an average serum concentration of 0.34 ng/mL. To investigate whether TBBPA induces adverse outcomes at environmentally relevant exposure doses, the mice were exposed to TBBPA for 14 and 28 days. The internal doses of TBBPA in mice serum were nearly the internal doses in volunteers. TBBPA significantly increased the secretion of some pro-inflammatory cytokines and suppressed immune responses in mice under such serum concentrations after 14- and 28-days exposure. Interestingly, uterine edema was observed in TBBPA-treated mice. In primary uterine cells model, the results showed TBBPA exposure suppressed THRβ expression, leading to the activation of the inflammatory PI3K/NF-κB signaling pathway. Our findings indicated that the uterus is the susceptible target organ of TBBPA and TBBPA exposure might increase risk of uterine cancer through deregulating inflammation pathways.
研究领域:
环境科学
·
毒理学
·
生殖健康
✓ 已验证
产品关联
DOI
PubMed
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2024
·
IF 6.3
Mei Wan,Congling Shi,Lei Chen,Lei Deng,Yueping Qin,Honglei Che,Jingyun Jing,Junyi Li,Xiaodong Qian
Ammonium polyphosphate (APP) is the most commercially valuable phosphorus-based flame retardant, but poor interaction with the polymer interface limits the flame-retardant efficiency. In this work, a new type of multi-layered nanomaterial coating APP (APP-PEI@MXene@ZIF-67) was prepared and introduced into thermoplastic polyurethane (TPU) polymers by a simple and green assembly strategy. The effects of different loading shells of modified APP on the flame retardancy of TPU composites were investigated, as well as their gas/condensed phase thermal degradation products and their flame-retardant mechanisms. The results showed that APP-PEI@MXene@ZIF-67 was more favorable for catalytic char formation than APP, and the residual char formed by its composites was denser and more continuous. Compared with the pure TPU, the pHRR, THR, pSPR, and TSP of TPU/APP-PEI@MXene@ZIF-67–2BL composites were decreased by 72.75 %, 87.25 %, 59.58 %, and 85.97 %, respectively, which significantly reduced the heat and smoke release during the combustion process. The gas-phase and condensed-phase flame retardant mechanisms synergized to construct a possible approach to address the fire risk and heat/smoke hazards of TPUs and promote the extensive application of TPU polymers.
研究领域:
材料科学
·
高分子科学
·
消防安全工程
✓ 已验证
产品关联
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
·
2022
·
IF 6.206
Yapeng Zheng,Kang Zhang,Yan Wang,Chao Ma,Zhou Gui
There has been a greatly extensive research interest in PMMA materials as alternatives to traditional glass. However, it remains tremendously challenging to integrate multiple functionalities into a PMMA material that can be diffusely applied to a flammable and complex scene. Herein, we fabricated a transparent, flame-retardant and high hardness coating based PMMA substrate through an in situ photo-polymerization by UV curing technology. The LOI test results showed that all coated PMMA obtained a good grade compared with pure sample, CPMMA-1 and CPMMA-4,5 can reach 24.5 and 24.0, respectively. The cone calorimeter experiment revealed that coated PMMA significantly enhanced fire safety, as the PHRR and THR values of CPMMA-1 were reduced by 48.6 % and 23.0 %, respectively. The FPI and FGI values of CPMMA-1 were 0.060 (m 2 ·s)/kW and 2.8 kW/(m 2 ·s) in comparison with 0.049 (m 2 ·s)/kW and 10.4 kW/(m 2 ·s) of pure PMMA. The large panel combustion test results revealed that CPMMA-1 and CPMMA-5 obtained the good fireproof property. Additionally, all coated PMMA achieved a satisfactory level about at least 3H and 3B level in hardness and adhesion test and were greatly improved compared with the pure sample. Furthermore, the coated PMMA can still maintain good transparency and visible light properties. Therefore, an innovative research idea and basis for the fabrication of flame-retardant PMMA materials are provided in this work. The manufacture of coated PMMA in this research provides a promising way and foresight into the design development for the next-generation of multifunctional fireproof PMMA materials.
研究领域:
材料科学
·
消防安全工程
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2022
·Vol. 33
·期 10
·3490-3500
·
IF 3.348
Wu Zhang,Weikang Xia,Yasheng Shi,Changlin Zhou,Ran Chen,Lei Wang,Jinqing Qu
Flame-retarded epoxy thermosets are highly desirable for electronics-related basic materials in the new-generation information applications. Herein, a DOPO-anchored benzothiadiazole flame retardant, namely DOPO-BTD , is designed and synthesized for P/N/S synergistic flame-retarded epoxy thermosets. DOPO-BTD possesses good thermal stability and excellent compatibility with the epoxy matrix. As reflected by UL 94 test, the DOPO-BTD coated EP passes the V0 rating and achieves a higher LOI value of 34.6% at ultralow P content of 0.39 wt%. The investigation of the DOPO-BTD -triggered P/N/S synergistic flame-retarded effect by thermal images further validated the flame retarded efficacy and dramatic inhibition of the flame. Meanwhile, the incorporation of 4.8 wt% DOPO-BTD into the epoxy matrix, the PHRR, THR, SPR, TSP, and COP are significantly decreased by 37.97%, 27.44%, 25.49%, 19.83%, and 31.70%, respectively. Additionally, the fire growth index (FGI) is sharply dropped 26.06%. Moreover, the TGIR and TGMS results convince the flame-retarded mechanism of DOPO-BTD through the combination of the gas-phase and condensed-phase pathways. The P/N/S synergistic DOPO-BTD can serve as a promising flame retardant for efficiently fabricating the flame-retarded epoxy thermosets, and this study sheds light on the development of multiple elements synergistic flame-retardants for functional polymers with great application potential.
研究领域:
材料科学
·
化学工程
·
高分子科学
✓ 已验证
产品关联
DOI
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2023
·
IF 3.4
Xiaodong Jin,Xinyi Wu,Qinyong Liu,Shibing Sun,Suping Cui,Sheng Zhang,Chen Chen
In this work, a metal organic framework (Fe-MOF) with the effect of absorbing toxic gases and good compatibility was synthesized by chelating a novel organic ligand contained carbonization groups (reacted by tris(hydroxymethyl) aminomethane and 1,4-piperazine dialdehyde) with iron salt. Then, it was used as the synergist to improve the efficiency of intumescent flame retardant (IFR) within polystyrene (PS) substrate. With the addition of 20% IFR and 2% Fe-MOF, the obtained PS composites exhibited a limiting oxygen index (LOI) value of 28.3% and a UL rating of V-0. Moreover, the peak heat release rate (pHRR), total heat release (THR), and total smoke production (TSP) of PS composites were decreased by 77.6%, 35.2%, and 33.7%, respectively. According to the mechanism analysis, it was found that Fe-MOF mainly acted in the condensed phase, contributing to the existence of dense char residues with the presence of IFR system. In addition, the good compatibility of organic ligand in Fe-MOF with PS substrate could partially alleviate the deterioration of mechanical properties due to the addition of IFR. For PS-20%IFR/2%Fe-MOF, the impact strength was improved from 1.7 kJ/m 2 (PS-22%IFR) to 2.2 kJ/m 2 , the tensile strength was also increased from 21.3 MPa (PS-22%IFR) to 22.4 MPa.
研究领域:
材料科学
·
高分子化学
·
消防安全工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2024
·
IF 2.7
Chao Ling,Wen Zhang,Zhengzhou Wang
The preparation of biomass flame retardants with efficient flame-retardant properties is conducive to the realization of sustainable development and is of great practical significance. In this work, a green and sustainable biomass flame retardant PATAPEI was prepared by using phytic acid (PA), tannic acid (TA), and polyethyleneimine (PEI) as reactants via a one-step method to develop biomass flame retardants that can synchronize enhanced flame retardation, smoke suppression, and mechanical performance of epoxy resin (EP). The EP with only a 3% PATAPEI (EP/3PTP) has a LOI value of 28.5% with a UL-94 V-0 classification. The peak heat release rate (PHRR), total heat release (THR), and total smoke release (TSR) of EP/3PTP were decreased by 29.72%, 25.80%, and 21.16%, respectively, in comparison with the ones of pure EP. Additionally, the tensile and impact strengths of EP/3PTP are higher than the ones of pure EP. PATAPEI on heating decomposes to produce phosphorus-containing acids and biphenyltriol-containing compounds, which promote to form a good char layer with the aromatic structures during the combustion of EP/3PTP. Therefore, PATAPEI has prospects of wide application in the development of sustainable biomass flame retardant EP.
研究领域:
材料科学
·
化学工程
·
可持续化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMOSPHERE
·
2022
·
IF 8.943
Jia-Hui Chen,Jia-Hui Lu,Xiao-Lu Pu,Li Chen,Yu-Zhong Wang
Flame retardancy and recyclability are two important issues in the research field of thermosets, particularly for epoxy resin (EP) with the biggest market share. It is of great importance, but rarely achievable, to integrate these properties simultaneously into EP. Herein, we report a facile way to prepare intrinsically flame-retardant epoxy vitrimers combining rapid recycling and multiple shape memory effects by introducing dynamic ester-linkages with catalytic transesterification activity into the crosslinking networks of EP. The flame-retardant epoxy vitrimers exhibited high T g (∼110.7 °C), desirable thermal stability and excellent flame retardancy with UL-94 V-0 rating, and high LOI of ∼34%. Also, the value of the peak heat release rate (PHRR) and the total heat release (THR) showed 63% and 32% reduction, respectively. Meanwhile, flame-retardant epoxy vitrimers showed high malleability that could be reprocessed in 15 min at 200 °C without sacrificing the mechanical properties and flame retardancy. Moreover, the dynamic transesterification network allowed flame-retardant EP to access multiple shape memory effect. The design of flame-retardant epoxy vitrimers provide a prime example to foster the cyclic utilization of flame-retardant thermosetting polymers.
研究领域:
材料科学
·
高分子化学
·
消防安全工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）